Re: Problems with 'class, help anyone?

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

Robert A Duff wrote:

> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:
> 
>> That's right, but there is a case where "function" really differs from
>> "procedure". I mean protected objects. ...
> 
> That's *another* example of basing things on a kludge.
> Certainly, it makes sense to distinguish read-only from read-write
> locking.  But to base that on "function" vs "procedure" is ...
> well, Yuck.

Absolutely

> Protected functions are *not* functions (in the maths sense),
> and therefore should not be so called.

Well, strictly speaking "+" is also not the mathematical +. Who cares. But I 
agree that protected function is not the best name for the thing.

>>... "function" vs. "procedure" for a
>> protected object could potentially mean different implementation and
>> performance. So I think that one should leave "function"s as they are,
>> and just allow procedures with results:
>> 
>>    procedure Foo (...) return Bar;
> 
> Yeah, and then eliminate the "function Foo..." syntax.
> That would solve the problem!
> 
> Slight incompatibility...  ;-)

I am not afraid of! (:-))

But we still need some keywords for:

1. Subroutine (=procedure)
2. Subroutine with no side-effects other than on the arguments (=?)
3. Subroutine with only one side-effect on the result (=?)

"function" in Ada is sort of 1. dressed as 3. (:-()

{1,2,3} is multiplied to:

A. Subroutine with no queue
B. Subroutine with a queue (entry)

Well together it makes 3x2=6 different variants!

And not to forget the "notation" axis:

i.   operational x+y
ii.  prefix (subroutines of protected objects, tasks, attributes)
iii. functional A(x,y)
iv.  aggregated (x,y,z) (should Ada have user-defined ones?)

-- 
Regards,
Dmitry A. Kazakov
www.dmitry-kazakov.de